Carbon-coated natural graphite has been prepared by thermal vapor decomposition treatment of natural graphite at 1000 degrees C. Natural gaphite coated with carbon showed much better electrochemical performance as an anode material in both propylene carbonate-based and ethylene carbonate-based electrolytes than "bare" natural graphite. The effect of carbon coating on the electrochemical performance was investigated by solid-state Li-7-NMR in conjunction with standard electrochemical techniques.